Studies on the loose part evaluation technique

Abstract

In nuclear power plants, a loose part can contribute to component damage and material wear by frequent impacting with other parts in the system. Detection of loose parts is very important for plants, and location and mass evaluation of the loose part is also important after detection of loose parts. In this study, the fundamental characteristics concerning the impact wave propagation speed, the maximum acceleration amplitude, and frequency spectra of the impact signal for the simulated loose parts were studied. These characteristics have been applied to the impact location, and the loose part mass estimation. It was confirmed that the “MESH” method, to estimate the impact position, and the loose part mass estimation by “FR” value, show good results.